[PATCH] D50591: [PGO] Control Height Reduction

[Hiroshi Yamauchi via Phabricator via llvm-commits]

yamauchi added inline comments.


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Comment at: lib/Transforms/Instrumentation/ControlHeightReduction.cpp:1727
+  OldBR->dropAllReferences();
+  BranchInst *NewBR = BranchInst::Create(NewEntryBlock,
+                                         cast<BasicBlock>(VMap[NewEntryBlock]),
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davidxl wrote:
> Is is possible for this be 'folded' into unconditional branch given the true predicate?
The true predicate is a placeholder. It will be replaced later in fixupBranchesAndSelects(). Added a comment.


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Comment at: lib/Transforms/Instrumentation/ControlHeightReduction.cpp:1730
+                                         ConstantInt::getTrue(F.getContext()));
+  PreEntryBlock->getInstList().push_back(NewBR);
+  assert(NewEntryBlock->getSinglePredecessor() == EntryBlock &&
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davidxl wrote:
> Is it better to use IRBuilder interface here?
I'll keep it here as is to be symmetric with the removal of the old branch instruction above. But I'll use IRBuilder in the other places (addToMergedCondition()).


Repository:
  rL LLVM

https://reviews.llvm.org/D50591